This invention relates to surgical blade units for use within the body and in particular to means for securing the portion of the device within the body against displacement from a handle under high force conditions.
It has long been recognized as desirable to employ handles and replaceable blade units in place of one-piece surgical scalpels to obtain the advantages of assured sharpness and sterility. Difficulties have been encountered in prior designs under high force conditions, especially where it is required that the unit be small. Particular problems have been encountered in arthroscopic surgery, i.e. surgery through a small puncture in the body in which the surgeon views the operative site by means of an arthroscope inserted via another puncture wound. The accidental detachment of a blade from a handle under such conditions is very undesirable.
The problem has perhaps been most serious with respect to reverse cutting involving pulling motions, such as retrograde scalpels in arthroscopic surgery.